Magnetic tape cassettes
US4974791A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 22, 1988 |
| Grant date | Dec 4, 1990 |
| Priority date | — |
| Expiry date | Jul 22, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B23/087
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic tape cassette has an improved reel spring, slack limiter and tape guide. The reel spring has a generally rectangular shape with first and second parallel edges extending substantially along its entire length. A flat, central base portion of the spring is bounded by a pair of transition portions which extend at an angle out of the plane of the base. A pair of outer end portions set at a sharper angle to the base complete the spring configuration. A polypropylene slack limiter applies a preloaded tension on the magnetic tape. The polypropylene eliminates the need for laminating a separate bearing material to the slack limiter. The tape guide has a semi-cylindrical, stainless steel insert attached to a plastic mounting core. The core is fastened to the cassette housing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.